The ability to discriminate spectral shape is an essential aspect of speech perception. Spectral shape determines vowel identity in speech and contributes to the perception of consonants. Improving spectral-shape sensitivity in users of cochlear prostheses might improve speech understanding. It is hypothesized that bipolar electrode configurations (BP) will provide better perceptual spectral resolution than monopolar (MP) configurations. The proposed study will evaluate place-pitch and spectral-shape sensitivity in users of Cochlear(R) 24R (CS) and 24M prostheses and determine the effect of different electrode configurations (bipolar and monopolar). Additionally, spectral-shape sensitivity will be evaluated as a function of the number of active electrodes. Finally, the ability of listeners to recognize vowels, consonants, and sentences in quiet and in noise will be evaluated. It is expected that BP configurations will, in general, yield better spectral resolution, and spectral sensitivity will be correlated with speech perception ability. Additionally, many listeners' spectral-shape sensitivities are expected to be superior with fewer active electrodes suggesting that their speech perception ability might be better with fewer active electrodes. The studies are also intended to form a firm foundation for controlled, parametric studies of spectral-shape sensitivity for evaluation of future prosthetic technologies.